Light-emitting devices using a light-emitting diode (LED) are widely used in optical devices such as display devices, display lamps, various switches, signal devices, and general illumination equipment for indoor use, outdoor use, stationary use, mobile use, and the like.
In a known example of such a light-emitting device, the light-emitting device is formed by sandwiching a plurality of LED elements between a pair of light transmissive and flexible insulating substrates and filling a light transmissive resin between the insulating substrates so as to embed the plurality of LED elements in a transparent resin.
In such a light-emitting device, electrical wiring for lighting the LED elements is also embedded together with the LED elements within the transparent resin. Therefore, the electrical wiring to be embedded also needs to be transparent and flexible. Thus, as the electrical wiring, for example, a mesh wiring formed by fine wires made of a material with relatively high conductivity such as silver, or transparent wiring formed by processing ITO (Indium Tin Oxide) film is used.
In order to operate such a light-emitting device, the electrical wiring must be electrically connected to an external power source or some other external devices (hereinafter referred to as an “external device, etc.”). However, the electrical wiring that has been embedded in the transparent resin is extremely thin, and thus it is difficult to directly connect an external device, etc. to such thin electrical wiring.